1. Field
The following description relates to a color filter array formed on an image sensor.
2. Description of the Related Art
Generally, a color filter array refers to a mosaic of color filters which are placed on an image sensor and filter light by wavelength range to capture color information.
A typical example of a color filter array is a Bayer pattern which is formed by repeatedly arranging a 2×2 array of pixels including a red pixel and a green pixel (RG) and a green pixel and a blue pixel (GB). The color filter array with the Bayer pattern can represent primary colors without any processing since it has red, green and blue pixels to obtain the primary colors of light. However, there is a loss of sensitivity in the image obtained by the color filter array using the Bayer pattern.
Recently, to overcome such drawbacks of the Bayer pattern color filter array, a color filter array having a transparent pixel substituted for one of RGB pixels has been introduced. The substituted transparent pixel passes light and infrared light. The white light and the infrared light that have passed through the transparent pixel are detected by an image sensor. A white light signal and an infrared light signal have wider wavelength ranges than individual RGB signals, and thus an image with improved sensitivity can be obtained using the combination of the white light signal and the infrared light signal. However, the use of infrared light to increase the sensitivity of an image may cause noise in the image due to infrared light components incident on color pixels.